There is no formal definition of Chip Size/Scale Package (hereinafter called CSP), but generally this refers to a semiconductor package (IC package) in which the package size is the same as or only very slightly larger than the chip size. The development of CSP technology is very important for promoting high-density mounting.
One prior art publication relating to CSP is International Publication WO95/08856. In this publication, the method is adopted in which a lead frame is mounted on a lead frame support (special-purpose jig), and the leads are cut respectively (one by one) by a special tool, while at the same time the severed leads are bent downward, and are connected to bonding pads of the IC chip.
With this method, a special jig or equipment is required, and additionally leads may easily be made bent during the bonding to the IC chip by the cutting of the leads.